Low water paper

Abstract

Provided is a low water paper product comprised of wood pulp having at least some of the water present in the amorphous regions of the cellulosic pulp fiber structure replaced with a polyhydroxy polymer. The preferred polyhydroxy polymer used to replace the water is polyvinyl alcohol. The resulting paper product exhibits improved dimensional stability, particularly when exposed to water or water vapor. Characteristics of the paper product make it quite suitable for use in transformers.

What is claimed is:  
     
         1 . A low water paper product comprised of wood pulp having at least some of the water present in the amorphous regions of the cellulosic pulp fiber structure replaced with a polyhydroxy polymer, such that the paper product is more rigid and dimensionally stable when exposed to water.  
     
     
         2 . The paper product of  claim 1 , wherein the polyhydroxy polymer is polyvinyl alcohol.  
     
     
         3 . The paper product of  claim 1 , wherein the wood pulp fiber is comprised of a Kraft pulp.  
     
     
         4 . The paper product of  claim 1 , wherein the amount of polyhydroxy polymer contained in the product ranges from 0.5 weight percent to 3.0 weight percent.  
     
     
         5 . The paper product of  claim 4 , wherein the amount of polyhydroxy polymer is at least 1.0 weight percent.  
     
     
         6 . A process for preparing the low water paper product of  claim 1 , which comprises exposing cellulosic pulp to a solution of the polyhydroxy polymer until at least some of the water present in the amorphous regions of the cellulosic pulp fiber structure are replaced with the polyhydroxy polymer.  
     
     
         7 . The process of  claim 6 , wherein the wood pulp is exposed to the solution of the polyhydroxy polymer for a period of time ranging from 1 to 120 minutes.  
     
     
         8 . The process of  claim 6 , wherein the wood pulp is soaked in a solution of the polyhydroxy polymer.  
     
     
         9 . The process of  claim 6 , wherein subsequent refining and formation of the paper product takes place once the exposure to the solution of the polyhydroxy polymer is complete.  
     
     
         10 . A transformer comprised of the paper product of  claim 1 .  
     
     
         11 . A transformer comprised of the paper product of  claim 2 .  
     
     
         12 . A transformer comprised of the paper product of  claim 4 .  
     
     
         13 . A transformer comprised of the paper product of  claim 5 .  
     
     
         14 . The process of  claim 6 , wherein the cellulosic pulp is first refined before exposure to the solution of the polyhydroxy polymer.  
     
     
         15 . A wood pulp having at least some of the water present in the amorphous regions of the cellulosic fiber structure replaced with a polyhydroxy polymer.  
     
     
         16 . The wood pulp of  claim 15 , wherein the pulp is comprised of northern pine Kraft pulp.  
     
     
         17 . The wood pulp of  claim 15 , wherein the amount of polyhydroxy polymer contained in the wood pulp is at least 1.0 weight percent.  
     
     
         18 . The wood pulp of  claim 15 , wherein the amount of polyhydroxy polymer contained in the wood pulp ranges from 1.0 to 3.0 weight percent.  
     
     
         19 . The wood pulp of  claim 15 , wherein the amount of polyhydroxy polymer contained in the wood pulp ranges from 1.5 to 2.5 weight percent.  
     
     
         20 . The wood pulp of  claim 15 , wherein the polymer is polyvinyl alcohol.